Z axis wobble (Page 2 of 3)

Analysing your Z movements in your g-code, there are only a couple of differences:

1. Skeinforge includes the Z position in every G1 command, even if it doesn't change. I can't see this making a difference.

2. The feedrate for the z -axis moves in Skeinforge is really slow (~540) vs Slic3r (4800). I checked a g-code file of mine that is currently printing without drama and my z feedrate is 6000.

The are only two places I can see where you could change this. One is in Repetier-Host under 'Printer Settings > Printer > Z-axis feed rate. Mine is set to 200.

The other is in Slic3r under 'Print Settings > Speed > Speed for non-print moves'. Mine is set to 100. I see yours is set to 80 which maintains our ratio of 4800 vs 6000.

If you wanted to try getting the 540 from the skeinforge g-code you could try changing this speed in Slic3r to 11 or 12. It will slow down the print a bit though for the moves where no plastic is coming out.

Perhaps you could do a test with the value set to 100 to match mine, and then 12 to replicate the skeinforge z moves?

I assume you are slicing with Skeinforge from Pronterface and Slic3r from Repetier-Host?

This is assuming that Z movement feedrate is to blame, it could be something else entirely.

I'm going to add that kisslicer seems to be adding ridges for me as well. I haven't quite gotten skienforge to replicate my slic3r profiles, but i've tested slic3r 9.3, 7.2b, and kisslicer, all of them have ridges. Kisslicer also is slightly different in that i am using a square fill pattern and filling every layer instead of every third, so those factors aren't it either.

I mean it may just be the crappy threaded rod still and no matter what I'm going to get banding. Time to look into some acme threaded rod...

Lawsy: results of my tests...

1. "Repetier-Host under 'Printer Settings > Printer > Z-axis feed rate. Mine is set to 200" - I just checked and mine is also set at 200.

2. "test with the value set to 100 to match mine" - the same ridges occur as before (yet another photo seems overkill)

3. "12 to replicate the skeinforge z moves" - the same ridges...though my beard is much longer now.

4. "I assume you are slicing with Skeinforge from Pronterface and Slic3r from Repetier-Host?" - I'm using the various versions of slic3r from within Repetier-Host. I've tried a few different versions of skeinforge and also use it from within Repetier-Host.

Thanks again for the suggestions. I'm still stumped.

Another suggestion is for me to try your exact slic3r configs and an object you have printed successfully. There is the outside possibility that I've changed an option somewhere that leads to this observation.

OK, here is something that might help. There is bug in Repetier that is very subtle, at least this happens consistently on my laptop. I think it might be memory leak since things start good but it shows up little later. Essentially what happens is that if while printing you leave the Manual Control tab selected after some time this will affect the output of G-Code to printer and can randomly stall it and slow it down generating essentially what you see.

I at first noticed this on my prints of shafts and have posted here thinking its Slic3r but it was not, its Repetier.

Solution was simple, after you start print Repetier will switch automatically to Manual Control tab. Switch to any other tab and let it print and you should be OK.

Give it a try I am interested to hear whether that helps. That fixed all issues on my side.

Okay, another update here - although still no closer to figuring this out...

I saw that Ian had posted his 0.1mm layer slic3r ini file as well as his settings for KISSlicer:
http://www.soliforum.com/topic/611/soli … -printing/

So, I gave them both a try (I altered Ian's layer height in this slic3r settings to be 0.2mm in order to retain parity with all the other tests I've carried out). You can see the results here:
http://www.flickr.com/photos/jenninaj/8 … hotostream

I printed a different model to highlight that this effect is not directly related to the specific object I'm printing.

Bottom line is that KISSlicer, like skeinforge, gives me a pretty smooth outline whereas any configuration of slic3r I've tried (including multiple versions of the software) produces pronounced ridges in the surface. Weirdorama, dudes.

Thanks, Ian. I can confirm that slic3r 0.9.7 is an improvement over other versions - the ridges are less pronounced. Still not quite as smooth as KISSlicer but definately workable.

How does one upgrade to Slic3r 0.9.7 within Repetier?  Will installing the new version separately simply perform the upgrade?
Sorry, I'm far from a computer guru!

If you install Slic3r, it may just replace what was there already and everything will work fine.  However, if for some reason you find that it doesn't work you go to preferences and open up the Slicer config element and then select Slic3r.  You will then be able to select the executable you want to use.

On OSX the preferences is reached by clicking on the Repetier-Host MAC menu Item and selecting Preferences.  I am not sure of the steps on Windows or Linux, but I imagine they will be similar.

I'm guessing he took the picture while the printer was running and you're seeing movement in the clear filament, or his hand was shaking.

@Mesh, great fix

Yeah, that's just my filament... I have just the stock set up for the filament. Only thing I did was put a piece of masking tape with the sticky side out on the frame to keep my filament taut and prevent the filament from reversing and unspooling all over the place.

Not particularly with the set up I have... I used a nut that had the nylon bushing/lock on it and had to carve all that crap out with an x-acto before I could put it on. There's a little bit left in the nut and loads of grease that solidoodle guys were so generous with, so the nut has a bit of resistance without a spring.

Honestly, I never thought of using a spring and sounds like a good idea though, especially with the nuts that don't have the nylon stuff inside. I'm sure if you found a spring that fit directly under the nut without protruding out of the sides, the nuthugger could keep everything in place. I made it so that it uses the notch in the wood and the 4 smaller nuts as a brace.

I think I'll try it, thanks for the idea Jonathan.

Did you change your Extrusion Multiplier after changing the extruder steps?

Also wobble isn't the only problem with Z, inconsistent movement up and down will create ridges all around.  The problem could be backlash, which is what the nut hugger is actually designed to fix.